Melee

Fist

With your fist, you have the choice of disarming, counteracting a move, ground punches and kicks, lefts and rights, and uppercuts and jabs. String moves together to create a combo. On some occasions you can preform "Stun" hits. Also, fighting unarmed is the best way to fight someone without killing them, something that can be important in several missions. The combos deal out the most damage. With fist selected as current weapon you can pick up random objects off the streets (such as a plank bottle etc..), you cannot switch weapons well an item is picked up, throw it away to switch.

Knife

Knives are very efficient alternatives to firearms. Even a well-armored adversary can be taken down with a few slashes. They are very efficient at taking someone down with out getting police attention. This is helpful on the street and in missions.

Bat

The bat can be swung left or right. You can also block attacks with it. The bat can be useful when you don't want to draw attention to yourself, since it is considered a "silent" weapon, though less so than the Knife.

Thrown Weapons

Molotov

The Molotov can only be thrown overhanded, which helps to ensure that you throw it far enough that you don't burn yourself. They are primarily an anti-personnel weapon; it takes several to destroy a car. It works well for drive-bys, too. Most pedestrians/cops will die once set on fire, but armored targets will only suffer mild damage. It works well when fighting N.O.O.S.E enforcers, because when they're flailing about on fire, you can shoot them easily. You can also just let them burn and drive away, even though shooting is probably your best bet.

Grenades

The Grenade is excellent at clearing rooms full of enemies and taking out vehicles. They can be tossed underhand when crouched behind a barrier, or overhand while standing. Be careful not to hit the cover you're hiding behind when you throw the grenade. You can "cook" (shorten the detonation timer) the grenade by holding the throw button. You can also drop these out of your car window to fend off pursuers. They cost $1,000 per grenade.

Firearms

Weapons can be purchased at a "Weapons" type store or Little Jacob once you have won over his friendship.

Handguns

Handguns are the staple to any crime dog's arsenal. Even in the endgame, pistols are very efficient guns. While generally not a good idea to try to kill someone by unloading into their body, you can make short work of them by shooting them in the head, foot or leg. Recommended for weaker enemies, as well as enemies that are disarmed or helpless.

Pistol (Glock)

Caliber: 9x19mm

Capacity: 17 (1183 rounds extra)

Developed in the 1980s by Austrian engineer, Gaston Glock, the eponymous pistol soon became the world's most popular civilian and law enforcement sidearm. With its polymer frame and simple, internal striker-fired mechanism, the Glock is both lightweight and extremely durable.

Combat Pistol (Desert Eagle)

Caliber: .357 Magnum (ingame)

Capacity: 9 (1191 rounds extra)

In 1979, Magnum Research Inc. set out to create the first gas-operated, magnum-caliber pistol. While the end product is generally considered too heavy and too expensive to serve as a practical combat pistol, it hasn't stopped the Desert Eagle from becoming the weapon of choice for Hollywood (and video game) bad guys. It is a powerful gun ingame, but has a small clip, forcing more frequent reloads.

Sub-Machine Guns

Submachine guns are the next step up from pistols. They're most effective a medium range. These are preferred over pistols when doing drive-bys or chasing down an escaping car, and are the strongest weapons that can be used while doing so.

Micro-SMG (Micro Uzi)

Caliber: 9x19mm

Capacity: 50 (1150 extra)

The smallest member of the Uzi family was introduced by Israel Military Industries in 1986 as a security weapon to fill the firepower gap between pistols and standard submachine guns. Between its short barrel and extreme rate of fire, things like aiming are but an afterthought. This gun is not as fast, accurate or powerful as the MP10, but it holds more bullets per clip.

SMG (SW MP-10)

Caliber: 9x19mm

Capacity: 30 (1170 rounds extra)

The SW10 is a derivative of the MP5, doing away with a buttstock and fitting a polymer grip. Otherwise, it retains the MP5's functionality and is a good weapon, although it has a high rate of fire and can burn through ammo quickly.

Assault Rifles

Assault Rifle (AK-47)

Caliber: 7.62x39mm

Capacity: 30 (570 rounds extra)

Even after sixty years, Mikhail Kalashnikov's legendary AK-47 rifle is still a hard act to follow; both in reliability and popularity. Created with mass production in mind, the simple design and loose clearances resulted in a rifle that's practically indestructible, and that will remain functional with little maintenance or cleaning. A much more powerful rifle than the HK416, but is more inaccurate to compensate.

Carbine Rifle (HK416 Carbine)

Caliber: 5.56x45mm NATO

Capacity: 30 (570 rounds extra)

The HK416 entered service in 2005 as a replacement for the Colt M4 in service with US military forces. The 416 was intended for use by second-line and special-operations troops. It is gas-operated and air-cooled, with a cyclic firing rate of 700 to 900 rounds per minute. Overall length is 31 inches (with stock extended) and the barrel length is 14.5 inches. The Carbine is slightly more accurate than the AK-47, but less powerful.

Sniper Rifles

Sniper Rifle (M40A1)

Caliber: 7.62x51mm NATO

Capacity: 5 (45 rounds extra)

The M40A1 started its life as a Remington 700, and was then customized by the US Marine Corps to fit their sniping needs. Strangely enough, the one in the game appears to have been further customized to use an external 10 round magazine, yet it only holds 5.

Combat Sniper (PSG1)

Shotguns

Pump Shotgun (Winchester Defender)

Gauge: 12

Capacity: 8 (72 shells max)

Based roughly on the classic Remington 870 (which is also featured in some artwork), the Winchester 1300 line is also known as the "Speed Pump" series thanks to the short, fast cycling of the action. This feature has made the shotgun popular for both sporting and security purposes.

Combat Shotgun (Beretta 1201 Automatic)

This automatic shotgun is a powerful tool for disposing of enemies quickly and efficiently. Although it burns through ammo quickly, it is useful for holding back enemies and saturating an area with large amounts of lead. Easily acquired, just enter a police cruiser, and a free one with 5 shells is given.

Rocket/Grenade Launchers

RPG-7

Caliber: 40mm

Capacity: 1 (8 extra)

This classic anti-tank, rocket propelled grenade launcher was first used by the Soviets back in 1961. It has remained popular ever since thanks to its durability and low cost. The RPG can even skip off the ground and knock things around that are in its way. This weapon costs $15,000 to purchase and $5,000 per rocket. Rockets fired at average sized cars will automatically destroy them. It is, by far, one of the deadliest weapons in the game.